Influence of sevoflurane anesthesia on expression of GAP-43 and NCAM in hippocampal neurons of neonatal rats

Abstract

Objective To evaluate the influence of sevoflurane anesthesia on the expression of growth-associated protein 43(GAP-43)and neural cell adhesion molecule(NCAM)in hippocampal neurons of neonatal rats. Methods Thirty-six pathogen-free Sprague-Dawley rats, aged 7 weeks, weighing 15-20 g, were randomly divided into 4 groups(n=9 each)using a random number table: control group(C group), 1.5% sevoflurane 6 h group(L group), 3% sevoflurane 2 h group(H1 group)and 3% sevoflurane 6 h group(H2 group). Group L inhaled 1.5% sevoflurane in oxygen for 6 h. H1 and H2 groups inhaled 3% sevoflurane in oxygen for 2 and 6 h, respectively.Group C inhaled 30% oxygen only.When the neonatal rats were 14 days old, the rats underwent Morris water maze test for 7 consecutive days.Place navigation and spatial probe tests were carried out.After the end of Morris water maze test, the rats were sacrificed, and the hippocampus was obtained for determination of the expression of GAP-43 and NCAM in hippocampal neurons. Results Compared with group C, the escape latency was significantly prolonged, the time of staying at the original platform quadrant was shortened, and the expression of GAP-43 was down-regulated in L, H1 and H2 groups, and the frequency of crossing the original platform was decreased in L and H2 groups.There was no significant difference in NCAM expression among the four groups. Conclusion The mechanism by which sevoflurane anesthesia decreases the cognitive function may be related to down-regulated expression of GAP-43, but not related to NCAM expression in hippocampal neurons of neonatal rats. Key words: Anesthetics, inhalation; Anesthesia; Infant; Cognition disorders; GAP-43 protein; Neural cell adhesion molecules; Hippocampus; Neurons